gecko-dev/gfx/2d/Quaternion.h

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZILLA_GFX_QUATERNION_H_
#define MOZILLA_GFX_QUATERNION_H_
#include "Types.h"
#include <math.h>
#include <ostream>
#include "mozilla/Attributes.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/gfx/MatrixFwd.h"
#include "mozilla/gfx/Point.h"
namespace mozilla {
namespace gfx {
template <class T>
class BaseQuaternion {
public:
BaseQuaternion() : x(0.0f), y(0.0f), z(0.0f), w(1.0f) {}
BaseQuaternion(T aX, T aY, T aZ, T aW) : x(aX), y(aY), z(aZ), w(aW) {}
BaseQuaternion(const BaseQuaternion& aOther) {
x = aOther.x;
y = aOther.y;
z = aOther.y;
w = aOther.w;
}
T x, y, z, w;
template <class U>
friend std::ostream& operator<<(std::ostream& aStream,
const BaseQuaternion<U>& aQuat);
void Set(T aX, T aY, T aZ, T aW) {
x = aX;
y = aY;
z = aZ;
w = aW;
}
// Assumes upper 3x3 of aMatrix is a pure rotation matrix (no scaling)
void SetFromRotationMatrix(
const Matrix4x4Typed<UnknownUnits, UnknownUnits, T>& m) {
// see
// http://www.euclideanspace.com/maths/geometry/rotations/conversions/matrixToQuaternion/index.htm
const T trace = m._11 + m._22 + m._33;
if (trace > 0.0) {
const T s = 0.5f / sqrt(trace + 1.0f);
w = 0.25f / s;
x = (m._32 - m._23) * s;
y = (m._13 - m._31) * s;
z = (m._21 - m._12) * s;
} else if (m._11 > m._22 && m._11 > m._33) {
const T s = 2.0f * sqrt(1.0f + m._11 - m._22 - m._33);
w = (m._32 - m._23) / s;
x = 0.25f * s;
y = (m._12 + m._21) / s;
z = (m._13 + m._31) / s;
} else if (m._22 > m._33) {
const T s = 2.0 * sqrt(1.0f + m._22 - m._11 - m._33);
w = (m._13 - m._31) / s;
x = (m._12 + m._21) / s;
y = 0.25f * s;
z = (m._23 + m._32) / s;
} else {
const T s = 2.0 * sqrt(1.0f + m._33 - m._11 - m._22);
w = (m._21 - m._12) / s;
x = (m._13 + m._31) / s;
y = (m._23 + m._32) / s;
z = 0.25f * s;
}
}
// result = this * aQuat
BaseQuaternion operator*(const BaseQuaternion& aQuat) const {
BaseQuaternion o;
const T bx = aQuat.x, by = aQuat.y, bz = aQuat.z, bw = aQuat.w;
o.x = x * bw + w * bx + y * bz - z * by;
o.y = y * bw + w * by + z * bx - x * bz;
o.z = z * bw + w * bz + x * by - y * bx;
o.w = w * bw - x * bx - y * by - z * bz;
return o;
}
BaseQuaternion& operator*=(const BaseQuaternion& aQuat) {
*this = *this * aQuat;
return *this;
}
T Length() const { return sqrt(x * x + y * y + z * z + w * w); }
BaseQuaternion& Conjugate() {
x *= -1.f;
y *= -1.f;
z *= -1.f;
return *this;
}
BaseQuaternion& Normalize() {
T l = Length();
if (l) {
l = 1.0f / l;
x *= l;
y *= l;
z *= l;
w *= l;
} else {
x = y = z = 0.f;
w = 1.f;
}
return *this;
}
BaseQuaternion& Invert() { return Conjugate().Normalize(); }
Point3DTyped<UnknownUnits, T> RotatePoint(
const Point3DTyped<UnknownUnits, T>& aPoint) {
T uvx = T(2.0) * (y * aPoint.z - z * aPoint.y);
T uvy = T(2.0) * (z * aPoint.x - x * aPoint.z);
T uvz = T(2.0) * (x * aPoint.y - y * aPoint.x);
return Point3DTyped<UnknownUnits, T>(
aPoint.x + w * uvx + y * uvz - z * uvy,
aPoint.y + w * uvy + z * uvx - x * uvz,
aPoint.z + w * uvz + x * uvy - y * uvx);
}
};
typedef BaseQuaternion<Float> Quaternion;
typedef BaseQuaternion<Double> QuaternionDouble;
} // namespace gfx
} // namespace mozilla
#endif